The British & Irish Lions face the toughest test of their tour so far against the Sharks in Durban on Wednesday night.

Unbeaten in their first three games, thanks to victories over the Royal XV, Golden Lions and Cheetahs, Ian McGeechan's side face a significant step up in class at ABSA Stadium against a side that just missed out on the Super 14 semi-finals but crucially they have been stripped of nearly all their Springboks.

The Lions will be favourites to extend their winning run but victory alone will not be sufficient at this stage of the tour. Time is running out for the Lions to settle on their ideal combinations with the first Test against the Springboks less than two weeks away. The narrow escape against the Cheetahs in Bloemfontein will have increased the pressure on the entire tour party to get it right sooner rather than later.

The Lions were second best at the breakdown last time out and as a result struggled to find the pace and power that allowed them to steam-roller the Golden Lions at Ellis Park. That fact will not have been lost on the Sharks, or the Springboks, and the tourists will be keen to reassert their class in that area of the game and limit the turnovers that blighted their performance.

McGeechan revealed this week that he is unlikely to field his best line-up before the first meeting with South Africa at the same venue on June 20 but his latest selection has a distinct Test look to it in certain areas. The decision to keep his preferred XV under wraps until the Test series does carry a sizeable risk but it is a gamble he is willing to take believing the element of surprise and squad morale outweigh any possible negatives.

Brian O'Driscoll and Jamie Roberts resume their partnership in midfield and a display akin to that which they produced in Johannesburg will cement their Test status and cause more concern for South Africa. The duo looked like a perfect fit in their first start alongside one another and their class should show again against the Sharks.

Elsewhere, a formidable back row combination of blindside Tom Croft, openside David Wallace and No.8 Jamie Heaslip looks more than capable of providing the kind of momentum that was lacking against the Cheetahs. Captain Paul O'Connell has a new second row partner in the athletic Alun Wyn-Jones while fullback Lee Byrne and wingers Shane Williams and Luke Fitzgerald are backing up from the Cheetahs clash like their skipper.

Fly-half Ronan O'Gara starts his second game and is under pressure to deliver if he wants to lay claim to the No.10 shirt for the opening Test. His control and kicking in the opening encounter against the Royal XV was good but he has since seen Stephen Jones and James Hook raise the bar yet further.

The Sharks will be without their big names for Wednesday's game, but coach John Plumtree has been able to call on international forwards Jannie du Plessis, Deon Carstens and Johann Muller. Rising star Steven Sykes will partner Muller in the second row while a formidable back-row trio of Jacques Botes, Jean Deysel and Keegan Daniel makes for a mouth-watering battle at the breakdown.

The lively Rory Kockott fills the No.9 jersey and will partner fly-half Monty Dumond while former Ospreys star Stefan Terblanche forms part of the Sharks' backline.

As with all of the Lions' provincial opponents, the Sharks have nothing to lose and everything to gain from their 'once in a lifetime' opportunity. Whether they rise to the challenge like the Cheetahs or fail to turn up like the Lions remains to be seen but either way they look desperately short of firepower.

They will miss their internationals and it is a shame that Springboks Ryan Kankowski and Odwa Ndungane were ruled out of the clash through injury having been released by coach Peter de Villiers.

The Lions should come away from Durban unscathed but a victory is far from a foregone conclusion. The Cheetahs caused many problems last time out, most notably at the breakdown, and the Sharks are sure to employ the same tactics that brought their Super 14 rivals to the brink of an historic upset.

Scrum time will also be a big indicator with two huge packs while referee Jonathan Kaplan's interpretation of the laws governing the breakdown will have been addressed by both sides following convern over Wayne Barnes' influence on last weekend's game.

In their 11 previous meetings the Lions have never tasted defeat against the Natal Sharks and their last defeat at ABSA Stadium, formerly known at Kings Park, was way back in 1962 in the first Test against the Springboks in the second Test.

Both those records are set to be intact for at least one more game but the Lions must show that they have learnt their less - time is a luxury they do not have.